The invention relates to a fuel supply device for mixture-compressing, externally ignited internal combustion engines with a throttle member arranged in the air intake manifold so as to be arbitrarily activatable, and an air metering member, which is deflected against a return force according to the air flow rate and thereby activates a fuel metering device. In addition, the fuel metering device has a control slit, which, in turn, opens a control groove to a greater or lesser degree to meter the fuel and the metered fuel quantity is injected into the air intake manifold, especially by means of a nozzle. A fuel supply device is already known in which only a relatively rough adjustment of the basic setting of the fuel metering device which belongs to the fuel supply device is possible. In addition, the rigid coupling between the air metering member and the fuel metering device does not allow the exchange or replacement of these individual assemblies to adapt to various internal combustion engine values. The danger also exists that a portion of the fuel may enter the air intake manifold upstream of the air metering member in an undesirable manner through the air line that is intended to supply air so as to better spread the fuel mixture.